[Doctor Stochastic]

You would be correct had you not overlooked the effects of gravity. Small objects, such as comet's tails do accelerate away from the Sun. The Earth doesn't.

Computations in detail.

[Fish Hunter]

Hi Doc,

Thanks for the insight. Using "your" own numbers. I subtracted the acceleration of gravity (5.92E-3 from the acceleration of the sunlight 6.79E-3 to yield a net positive outward acceleration of 8.7E-4 m/s^2. This makes sense because if it was not true then solar sails would not work and comet tails would not point away from the sun, agreed.

OK, put that acceleration into Newton's constant acceleration equation, x = x0 + v0*t + 0.5*a*t^2, with x=0 and v0=0 and t=1 billion years. You get an outward orbital change of 4.3E29 meters! Your number ends up bigger than mine :)

Argue with me all you want, but the FACTS are:

1 - The Earth orbits around the sun in a vacuum. Orbital mechanics tells us its orbit is constant WITHOUT any external force being applied to it.
2 - Light emitted from the Sun produces an outward force. Comet tails pointing away from the sun and solar sails attest to this.
3 - A billion years is a lot of seconds, then you gotta square it to make it bigger.
4 - Whatever acceleration number you use, will give you a massive change in orbit over a billion years, because a billion years is a lllloooonnnngggg time.

There is no way the Earth's orbit has been constant for a BILLION years because whatever kinetic energy it had at time 0 will increase over time as it absorbs light energy in 1 direction (outward). The solar system is not static because the fusion furnace of the sun is slowly pushing everything away from it. The fact that we do NOT see everything spiraling away from the sun at a high velocity is PROOF that the solar system is not even millions of years old.

F H

[VadeRetro]

computations in detail

Rats! You hadda go spoil the amateur hour catfight with some real professional doing the real number-crunching!